Motor vehicle heat exchangers for cooling engine coolant, refrigerant vapor and transmission oil are known. Most heat exchangers are comprised of a separate header and tank which are clamped to one another and brazed for sealing same. One type of heat exchanger is illustrated in U.S. Pat. No. 4,945,635 which discloses a method of making brazable pipes and heat exchanger. The tank is formed by rolling a brazing sheet into a cylinder with opposite ends being butt jointed to each other by brazing. Slots are provided in the tank for receiving the tube passes therein which communicate the engine fluid between the parallel tanks.
Granetzke U.S. Pat. No. 4,960,169 issued Oct. 2, 1990 discloses a baffle for a tubular heat exchanger header. The tanks are formed as essentially cylindrical tubes with slots formed therein to receive the plurality of parallel tube passes extending between the tanks.
Halstead et al U.S. Pat. No. 5,009,262 issued Apr. 23, 1991, and assigned to the assignee of the subject invention, discloses a combination radiator and condenser heat exchanger for a vehicle. The heat exchanger includes a pair of tanks formed of a unitary extrusion with tube passes in fluid communication between the tanks.
In all the prior art patents, the ends of the tube passes are cutoff in a straight, rectangular configuration.